Low birth weight is associated with altered immune function in rural Bangladeshi children: a birth cohort study

Abstract

Background: Low birth weight is generally an outcome of a fetal insult or nutritional insufficiency. Recent studies have shown that such exposure early in life may have long-term implications for later immunocompetence and susceptibility to infectious diseases. Objective: We aimed to investigate the effect of birth weight on immune function in preschool-age children. Design: A birth cohort cross-sectional study was conducted in children (n ҃ 132) aged 60.8 Ȁ 0.32 mo who were born in Matlab, a rural area of Bangladesh, and whose weight and length were measured within 72 h of birth. The outcome measures were thymopoiesis, T cell turnover, acute phase response, and percentage of lymphocytes. Results: Children born with low birth weight (2500 g; LBW group, n ҃ 66) had significantly higher concentrations of T cell receptor excision circles in peripheral blood mononuclear cells-a biomarker for thymopoiesis-and significantly higher serum bactericidal activity and C-reactive protein concentrations than did children born with normal birth weight (ͧ2500 g; NBW group, n ҃ 66) (P 0.05 for both). The LBW group children had significantly lower concentrations of interleukin 7 in plasma (P ҃ 0.02), shorter telomere length in peripheral blood mononuclear cells (P ҃ 0.02), and a lower percentage of CD3 T cells (P ҃ 0.06) than did the NBW group children. Conclusions: Greater peripheral T cell turnover (shorter telomeres and lower CD3 concentrations) due to immune activation (elevated C-reactive protein concentrations and bactericidal activity) may have resulted in a greater need for replenishment from the thymus (higher T cell receptor excision circles); these events may cause lower immune functional reserve in preschool-age children born with LBW. Thus, LBW has implications for immunocompetence and increased vulnerability to infectious diseases in later life.Am J Clin Nutr 2007;85:845-52.

Stress exposure in intrauterine life is associated with shorter telomere length in young adulthood

“…1). Birth weight percentile (birth weight adjusted for gestational age at delivery) also was significantly associated with LTL [β = 0.002; 95% CI = 0.000 to 0.003; P < 0.05), replicating an association that has been previously reported (39). Results from the fully adjusted multivariate regression model [that, in addition to prenatal stress exposure, included subject characteristics (e.g., age, BMI sex), birth weight percentile, postnatal early-life adversity (e.g., early trauma, maternal care), and exposure to concurrent life stress (e.g., chronic stress, depressive symptoms)] indicate this adjustment produced a small increase in the prenatal stress coefficient (β = −0.090; 95% CI = −0.179 to −0.001; P < 0.05).…”

“…In humans, telomeres in placental trophoblasts are found to be shorter in pregnancies complicated with intrauterine growth restriction (38). Last, one study in preschoolage children found that children who were born low birth weight had shorter leukocyte telomere length (LTL) than age-matched children who had a normal birth weight (39).…”

Preterm neonates show marked leukopenia and lymphopenia that are associated with increased regulatory T-cell values and diminished IL-7

“…In preterm infants, we found a deficiency of IL-7 that has also been observed in low-birth-weight neonates (26). IL-7 is essential for the survival of T cells, especially RTEs.…”

Effect of fetal and child health on kidney development and long-term risk of hypertension and kidney disease

“…Premature senescence in the kidney may result from ongoing hyperfiltration injury in kidneys with fewer nephrons, compounded by a rapid increase in body size. In humans, leukocyte telomere length was not different between LBW and NBW British newborns, but among 5 year old children from Bangladesh, telomeres were significantly shorter in those who were of LBW 93,94 . Senescence is linked to oxidative stress.…”